Brain metabolism of carbohydrates, water and electrolytes will be evaluated in animal models of human disease states which involve abnormalities of carbohydrate metabolism and can cause coma. Such disease states will include diabetic keto-acidosis, non-ketotic coma, hypoglycemia, and cerebral edema complicating each of the aforementioned. Animal models have been developed for all of the above. The parameters to be evaluated include Na, K, Cl, glucose, lactate, amino acids, Osm, intracellular PH, sorbitol, ketones and water content of the brain. Abnormalities present in the central nervous system of the animal models will be compared to the appropriate controls. Such comparisons should permit a synthesis of the pathophysiology of the disease state(s). When this has been done, appropriate therapeutic modalities will be evaluated.